Nokia developing the never-charge handset

Although only capable of harvesting 50mW - at best - from the airwaves, Nokia believes the new energy could keep a simple mobile running indefinitely.

If – like me – you have a tendency to forget to put your beloved mobile 'phone on charge each night, Nokia might just be about to answer your most fervent dreams: a handset which runs on fairy dust and dreams.

Okay, so the handset requires perhaps a little more than that: according to an article over on CNet, the Finnish mobile giant's latest wheeze is a mobile which absorbs free energy out of the air in the same way as an RFID tag.

The technology – currently being condensed into prototype form by Nokia's Cambridge-based Research Centre – snags free energy by absorbing the ever-present radio waves that surround us: TV signals, radio signals, even WiFi hotspots. By converting this excess energy into internal power, the handset will – the team believes – be able to absorb upwards of 50 milliwatts of power.

While 50mW might sound like a vanishingly small amount – and it is, although far higher than the 5mW that current lab experiments have yielded – it's more than a simple handset would need to keep itself running. A basic handset would require around 20mW to stay in standby – allowing the excess 30mW to be used in the trickle-charging of the device's battery. Okay, so it'll take a while to charge – but it can be charging all the time.

It's a neat idea, but not one we'll be seeing commercialised immediately: the researchers have said that it won't be developed into a usable solution for at least three years – more realistically, five. Despite the clear barriers to the technology, it has at least been proven as a concept in the increasing uses of passive RFID tags, which harvest radiowaves and convert them to enough energy to transmit their own unique code.

Tempted by the thought of a mobile 'phone you never need to charge, or are you slightly suspicious as to how long a 50mW current could keep your smartphone running for? Share your thoughts over in the forums.

Originally Posted by robyholmesDoes this not decease the signal? Surly the power has to be taken from somewhere, so the signal its feeding on with be reduced?

My understanding is that its really using power which would other wise have dissipated or been absorbed into the environment. You would have to have your antenna in the shadow of the phone to notice any drop in signal strength.

If i'm correct you'd need to think of this like a solar array. The same amount of radiation is emitted and no amount of solar panels will make the sun "use more power" but if your standing under a solar panel it would be dark and there would be little or no energy behind the panel but beside the panel there is the same amount of energy as is hitting the panel. Of course this is a little simple since radio waves "bend" more readily than light waves.

Even if you can't get a phone to never need charging, anything that extends the battery life is good. If this can be coupled with a wireless charging pad style thing for more rapid charging (like electric toothbrush chargers that don't require metal to metal contact) then charging lots of devices off one pad on your desk is definitely the way forward. It also opens up being able to have completely sealed phones which are robust to complete submersion which will be nice for those of us who do extreme sports!

Another thing would be to use a kinetic generator much like kinetic watches, I guess the current implementations don't generate much power, however add several of these small current generating devices together and it won't be long before even power thirsty smartphones won't need charging.

Originally Posted by tank_riderEven if you can't get a phone to never need charging, anything that extends the battery life is good. If this can be coupled with a wireless charging pad style thing for more rapid charging (like electric toothbrush chargers that don't require metal to metal contact) then charging lots of devices off one pad on your desk is definitely the way forward. It also opens up being able to have completely sealed phones which are robust to complete submersion which will be nice for those of us who do extreme sports!

Another thing would be to use a kinetic generator much like kinetic watches, I guess the current implementations don't generate much power, however add several of these small current generating devices together and it won't be long before even power thirsty smartphones won't need charging.

Originally Posted by thehippozas long as it doesn't look like that phone in the article

That's probably the type of phone you'd have to have to draw only 20mW...

I'm sure it would interfere anyway, regardless of whether it only draws 'spare' radiowaves from the air, there's no way it would be able to tell, so if it truly absorbed these waves, there would likely be massive interference? Or am I seriously dumbing it down? :o

well think like a crystal radio- it's free power.. there is small power there if they can use it to trickle charge the battery.. just wonder if it will be necessary with advances in battery life- I imagine if the phone is efficient enough and could recharge fully overnight.. that would be pretty slick- next best thing to superconductors I guess.. I want a phone that doubles as a fast mass storage device 1tb+ using bluetooth along with gps and all the other goodies.. it's coming someday

if you use the phone in a public place, wont you be 'shadowing' most of the spectrum? shadowing other people's phones, rifd tags, bluethoot, wifi,.... if it is one phone, i assume there is not really a problem. but take a 500 people? in an airport, a shopping mall, a rock concert?

I think you will find that it does degrade the signal. There was a case I remember where a guy was near a TV transmitter and he was using it to power his house. They found him because people complained that about 5:50 when he got home from work and started turning things on their TV signal go very bad.

I think that steveo_mcg is probably correct in that it's only in the shadow of the phone that would be affected, but you have to remember that most of these signals rely on bouncing off of things to get everywhere. So the signals that are absorbed by the phone won't be bouncing around to somewhere else which means that if everyone started using these phones we would have some problems.

This is all off the top of my head and I am quite willing to believe that I am wrong about some of that, but it's my understanding at this current point in time.

Your mobile phone's antenna absorbs lots of radio-waves. It picks up all signals in the proper frequency range just to see if they were meant for it. Most of them aren't and the energy is simply wasted. A radio signal consists of data signal and a carrier wave. Even on important signals, most of the signal and the carrier wave is just dissipated into heat.